Mirna reports new preclinical data of miRNA-based therapeutic candidate for hepatocellular carcinoma

Mirna Therapeutics, Inc., a biotechnology company pioneering microRNA replacement therapy for cancer, announced the presentation today of new preclinical data on the development of a miRNA-based therapeutic candidate for primary liver cancer at the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics in San Francisco, CA. The data were simultaneously presented at the 2011 CPRIT Innovations in Cancer Prevention and Research Conference in Austin, TX.

In a poster entitled "The Development of a miRNA-based Therapeutic Candidate for Hepatocellular Carcinoma," Mirna scientists showed that mimics of five tumor suppressor miRNAs, including miR-34 and let-7, all significantly inhibited the growth of liver tumors compared to animals treated with formulated negative control miRNAs. The five miRNA mimics were complexed with a lipid nanoparticle delivery formulation and injected into NOD/SCID mice with orthotopically grown Hep3B human liver cancer xenografts.

Preliminary studies indicate that the formulated miRNAs are neither toxic nor immunostimulatory. The formulated miRNAs are currently being evaluated for therapeutic activity in mouse models of other cancers and a development program has been initiated in anticipation of creating candidates for clinical cancer therapy.

The outstanding efficacy produced by miRNA replacement therapy results from the capacities of miRNAs to regulate multiple cancer-related genes and pathways. As a key part of the p53 tumor suppressor pathway, miR-34, for instance, regulates the expression of MET, MYC, RRAS, Notch, WNT, and other oncogenes.

"These data contribute to the mounting evidence that miRNA replacement therapy holds significant promise as a new approach to the treatment of cancer, and adds to our previous work showing that there are multiple potential delivery approaches that can be successfully employed to deliver Mirna's proprietary microRNAs to orthotopically grown tumors," said Dr. Paul Lammers, President and Chief Executive Officer of Mirna Therapeutics.